When Hazrat Mahdi (as) appears, all the sects will swear allegiance to him, because Hazrat Mahdi (as) is the greatest guide of the Islamic world

Hazrat Mahdi (as) is the greatest guide, saint and pole of the End Times. He is also the guide of Imam Rabbani, Abdulqadir Gaylani, all Sunni scholars and of the imams of all schools and of all sects. Therefore, Hazrat Mahdi (as) is also the guide of Mahmud Hodja Effendi. In one sermon, Cubbeli Ahmad prays to Allah, beseeching Him for the coming of Hazrat Mahdi (as). He begs Allah to be able to see Hazrat Mahdi (as).

This means that when Hazrat Mahdi (as) comes, both Mahmud Hodja and Cubbeli Ahmad and all the other sects and their members will follow Hazrat Mahdi (as) and accept his succession (spiritual leadership). There will be no community that rejects this oath of allegiance or maintains any other position when Hazrat Mahdi (as) appears.
Since Hazrat Mahdi (as) is the greatest guide, saint and pole of the End Times, all the sects will coalesce around him when he appears. Aware of this, and with our entrance into the End Times, many leaders of schools have abandoned the custom, which they had maintained for hundreds of years previously, of handing down the sacred trust of the succession (spiritual leadership) to the next person in line. For example, Ali Haydar Effendi relinquished his succession (spiritual leadership) to Hazrat Mahdi (as). Mahmud Hodja Effendi is currently Ali Haydar Efendi’s deputy. As of Hijri 1400, the time of the coming of Hazrat Mahdi (as), all the schools have begun awaiting his coming and natural guide.